Portal de Periódicos da CAPES

Application of light‐emitting diodes in bioreactors: Flashing light effects and energy economy in algal culture (Chlorella pyrenoidosa)

1996; Wiley; Volume: 50; Issue: 1 Linguagem: Inglês

10.1002/(sici)1097-0290(19960405)50

1097-0290

Hans C. P. Matthijs, Hans Balke, Udo M. van Hes, Bernd M. A. Kroon, Luuc R. Mur, Roger A. Binot,

Algal biology and biofuel production

Biotechnology and BioengineeringVolume 50, Issue 1 p. 98-107 Article Application of light-emitting diodes in bioreactors: Flashing light effects and energy economy in algal culture (Chlorella pyrenoidosa) Hans C. P. Matthijs, Corresponding Author Hans C. P. Matthijs a417hcpm@HORUS.SARA.NL Department of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsDepartment of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsSearch for more papers by this authorHans Balke, Hans Balke Department of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsSearch for more papers by this authorUdo M. van Hes, Udo M. van Hes Department of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsSearch for more papers by this authorBernd M. A. Kroon, Bernd M. A. Kroon Department of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsSearch for more papers by this authorLuuc R. Mur, Luuc R. Mur Department of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsSearch for more papers by this authorRoger A. Binot, Roger A. Binot rbinot@estec.esa.nl ESA/Estec, European Space Research and Technology Centre, P.O. Box 299, 2200 AG Noordwijk, The NetherlandsSearch for more papers by this author Hans C. P. Matthijs, Corresponding Author Hans C. P. Matthijs a417hcpm@HORUS.SARA.NL Department of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsDepartment of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsSearch for more papers by this authorHans Balke, Hans Balke Department of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsSearch for more papers by this authorUdo M. van Hes, Udo M. van Hes Department of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsSearch for more papers by this authorBernd M. A. Kroon, Bernd M. A. Kroon Department of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsSearch for more papers by this authorLuuc R. Mur, Luuc R. Mur Department of Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The NetherlandsSearch for more papers by this authorRoger A. Binot, Roger A. Binot rbinot@estec.esa.nl ESA/Estec, European Space Research and Technology Centre, P.O. Box 299, 2200 AG Noordwijk, The NetherlandsSearch for more papers by this author First published: 5 April 1996 https://doi.org/10.1002/(SICI)1097-0290(19960405)50:1 3.0.CO;2-3Citations: 170AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Abstract Light-emitting diodes (LEDs) were used as the sole light source in continuous culture of the green alga Chlorella pyrenoidosa. The LEDs applied show a peak emission at 659 nm with a half-power bandwidth of 30 nm. Selection of this wavelength range, which is optimal for excitation of chlorophylls a and b in their “red” absorption bands makes all photons emitted potentially suitable for photosynthesis. No need for additional supply of blue light was found. A standardized panel with 2 LEDs cm−2 fully covered one side of the culture vessel. At standard voltage in continuous operation the light output of the diode panel appeared more than sufficient to reach maximal growth. Flash operation (5-μs pulse duration) enables potential use of higher operating voltages which may render up to three times more light output. Flat airlift fermentor-type continuous culture devices were used to estimate steady state growth rates of Chlorella pyrenoidosa as a function of the light flux (μmol photons · m−2 · s−1) and the flashing frequency of the light-emitting diodes (which determines the duration of the dark “off” time between the 5-μs “on” pulses). At the fixed voltage and turbidostat setting applied a 20-kHz frequency, which equals dark periods of 45 μs, still permitted the maximum growth rate to become nearly reached. Lower frequencies fell short of sustaining the maximal growth rate. However, the light flux decrease resulting from lowering of the flash frequency appeared to reduce the observed growth rates less than in the case of a similar flux decrease with light originating from LEDs in continuous operation. Flash application also showed reduction of the quantum requirement for oxygen evolution at defined frequencies. The frequency domain of interest was between 2 and 14 kHz. LEDs may open interesting new perspectives for studies on optimization of mixing in mass algal culture via the possibility of separation of interests in the role of modulation on light energy conversion and saturation of nutrient supply. Use of flashing LEDs in indoor algal culture yielded a major gain in energy economy in comparison to luminescent light sources. © 1996 John Wiley & Sons, Inc. Citing Literature Volume50, Issue15 April 1996Pages 98-107 RelatedInformation